Effects of scatter correction processing on image quality of portable thoracic radiography in calves

Thoracic radiography provides diagnostic assistance in assessing the severity of lung lesions in bovine respiratory diseases. We investigated the effects of a novel scatter correction processing software on the image quality of portable thoracic radiography in calves: this scatter correction method was recently developed for mobile bedside chest radiography in humans. Thoracic radiographs of the caudodorsal region were obtained from 30 calves of various sizes. Scatter correction processing of a grid ratio of 3 : 1 or 8 : 1 was applied to each image. The delineation of caudal thoracic vertebral bodies, scapulae, proximal third of the ribs, pulmonary vessels, and the aortic arch, as well as overall image quality were graded by five veterinarians using 5-point scales. Three types of images (original and scatter-corrected with grid ratios of 3 : 1 and 8 : 1) were compared using visual grading characteristics analysis. Scatter correction with a grid ratio of 3 : 1 improved the overall image quality, at least for calves with a body thickness of ≤40 cm, and improved the delineation of some anatomical structures for larger calves. Scatter correction with a grid ratio of 8 : 1 did not improve the delineation of any anatomical structures examined for calves ＞40 cm in thickness or the overall image quality for calves ＞30 cm in thickness. The present findings support the efficacy of scatter correction processing with a grid ratio of 3 : 1 for portable thoracic radiography in calves

Evaluation of grid performance for thoracic radiography in calves using a portable x-ray unit

Thoracic radiography provides diagnostic assistance in assessing the severity of lung lesions in bovine respiratory diseases. We investigated the effects of grid use on overall image quality for portable thoracic radiography in calves. Thoracic radiographs of the dorsocaudal region were made for 30 calves of various sizes, using three acquisition techniques (digital radiography with no grid, with a 3 : 1 grid, and with an 8 : 1 grid). Overall image quality was graded independently by five veterinarians using a 5-point scale based on the visibility of the thoracic vertebral bodies, thoracic spinous processes, scapulae, proximal third of the ribs, caudal lobar pulmonary vessels, and aortic arch; and on the level of image noise. The results were evaluated using Visual Grading Characteristics analysis. The 3 : 1 grid significantly improved overall image quality, regardless of body size. The 8 : 1 grid improved image quality only for calves smaller than 30 cm in thickness. The results of this study support the value of a 3 : 1 grid for portable thoracic radiography in calves

<i>LINE-1</i> Methylation Status in Canine Splenic Hemangiosarcoma Tissue and Cell-Free DNA

Splenic hemangiosarcoma is one of the most common malignant tumors in dogs, and early diagnosis is of great importance for achieving a good prognosis. DNA methylation plays an important role in cancer development. Long interspersed nuclear element 1 (LINE-1) is the most abundant repetitive element in the genome. LINE-1 hypomethylation has been shown to be related to carcinogenesis in humans, and it has been used as a novel cancer biomarker. This study aimed to evaluate the methylation status of LINE-1 in tumor tissue and circulating cell-free DNA and assess its clinical significance in canine splenic hemangiosarcoma. Genomic DNA was isolated from splenic masses of 13 dogs with hemangiosarcoma, 11 with other malignant tumors, and 15 with benign lesions. LINE-1 methylation was quantified using methylation-sensitive and -insensitive restriction enzyme digestion followed by real-time polymerase chain reaction. Additionally, blood samples were collected from eight patients to isolate cell-free DNA to determine LINE-1 methylation status changes during the treatment course. LINE-1 methylation in tumor samples was significantly lower in patients with hemangiosarcoma than in those with other malignant tumors and benign lesions. Non-significant but similar results were observed for the cell-free DNA samples. Our results demonstrate that LINE-1 methylation status is a potential biomarker for splenic hemangiosarcoma

Gene and protein expression of a soluble form of CTLA-4 in a healthy dog

Cytotoxic T lymphocyte associated gene-4 (CTLA-4) is a costimulatory molecule, expressed on the surface of activated T cells that negatively regulates T cell activation. In humans, alternative splicing of the CTLA-4 gene generates two major isoforms of mRNA, and a soluble form of CTLA-4 (sCTLA-4) was detected in normal human serum. We describe alternatively spliced mRNA expressed in peripheral blood mononuclear cells obtained from a healthy dog lacking the transmembrane domain coded by exon 3 of the CTLA-4 gene. Immunoprecipitation and western blotting of dog serum revealed a band of approximately 23-kDa, which is consistent with the predicted size, based on the amino acid sequence of the canine sCTLA-4 obtained in this study

Three-legged radiographic view for evaluating cranioventral lung region in standing calves with bovine respiratory disease

This study proposed a novel radiographic positioning in order to image the cranioventral lung region using a portable X-ray unit and digital radiography system. In the novel position, calves were restrained in a chute and a unilateral forelimb was pulled cranially with the contralateral forelimb tied to the chute; the forelimbs were then spread cranio-caudally as in a scissor position (Three-legged view: TL view). In a preliminary study, we applied the TL view for imaging of 14 clinically healthy calves. In a clinical study, accuracy in detecting cranioventral lung lesions was compared between the standard standing view and the TL view for 19 calves, which were culled from herd; the results of postmortem examination were used as gold standard. Seven evaluators independently interpreted the images. The median (range) number of trials and the time for obtaining optimal position were 2 (1-7) and 263 sec (105-488), respectively in 14 healthy calves. Calves thicker than approximately 40 cm were not considered candidates for TL view in this setting because of difficulty in restraint and the low output of the portable X-ray unit. The TL view improved the detection of consolidation in the cranioventral lung region, compared with the standard view. The TL view was considered an optional view when the cranioventral lung region was an area of interest, because this view was relatively easy to perform and required a small number of personnel, even for large calves